That sounds like a great idea
i think the real adoption hinderance as of now is, player required to first buy bitcoin and then to buy GAME rather than simply buying GAME with paypal or credit card. I know developers said they would be intergrating this but if adoption is your goal, IMO this should be first priority.
Although i like your idea of distributing GAME for free matches. Free GAME (dust amount) for players to play around would be good too.
As for the question about prizes. GameCredits has the ability to monetize a number of games. In essence, we could (and are planning) gaming tournaments where individuals can play to win thousands of GAME. Any early tournament will again, be a test of our system polishing off any bugs. That way, when we offer our solution to developers, they can start doing paid tournaments of their own. Hope that makes sense!